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present
time than those prepared in Germany. There seems to be no good reason
for this, however, as the latter can be so skillfully made that it is
impossible to distinguish them from the Oriental stones.
Jasper includes
in general nearly all varieties of impure, opaque, colored,
crypto-crystalline quartz. In color it may be red, yellow, green,
brown, bluish, and black. To many of the pebbles found on almost any
sea or lake shore, or in the beds of streams, the name jasper may
properly be applied. If it occurs banded, that is, in stripes of
different colors, it is known as ribbon jasper. The different colors of
jasper are due to different impurities which it contains. These may be
clay, iron oxides, or organic matter, and at times reach a quantity as
high as twenty per cent. The color often varies irregularly in a single
stone, giving different effects, and sometimes imitating paintings.
Jasper which can be used in the arts is very widely distributed. Good
red jasper is obtained in Breisgau, and near Marburg in Germany. Much
brown jasper comes from Egypt. What is known as " Sioux Falls jasper,"
from Sioux Falls, South Dakota, is chiefly of a brown color. This stone
was highly prized by the Indians for its color, and is the " jasper "
referred to by Longfellow in Hiawatha:
"
At the doorway of his wigwam Sat the ancient Arrow-maker In the land of
the Dacotahs, Making arrow-heads of jasper, Arrow-heads of chalcedony."
The
yellow jasper used for mosaics comes chiefly from Sicily, but as good
could be obtained in many places in our own country. The green jasper
of the present time is obtained chiefly in the Urals, and is to a
considerable extent worked there into ornamental pieces. The Chinese
prize green jasper highly, the seal of the emperor being made from it.
Some jasper of a bluish shade is found in nature; but that of a deep
blue tinge is always artificially colored by Prussian blue. It is then
sometimes known as "false lapis"; that is, false lapis lazuli. Ribbon
jasper is found in Saxony, but chiefly comes from the Urals. The
qualities which make jasper of use in the arts are its color, opacity,
and capacity for taking a polish. At the present time it is not much
used except for mosaic work, and for small boxes, vases, and dishes.
The ancients, however, prized it highly and used it extensively. It is
one of the stones prescribed in the Book of Exodus to be worn in the
ephod of the high priest, and also forms one of the gates of the Holy
City, as described by St. John in Revelations. It is probable that the
jasper referred to in these instances was of a dark green
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